Induction-motor.



No. 872,708.. PATENTED DEC. s, 1907. B. A. BBHREND. INDUCTION MOTOR.

APPLICATION FILED -AUG- 31. 190B.

INVENTOR ATTORNEY Bernard A.'Behrend UNITED STATES PATENT BERNARD A. BEHREND, or NORWOOD, OHIO, ASSIGNOR TO ALLIS CHALMERS oonrinvia CORPORATION OF NEW JERSEY, AND THE PANY, A CORPORATION OF OHIO.

INDUCTION-MOTOR.

and useful Improvements in Induction Motors, of which the following is a full,

clear, and exact specification.

My invention relates to induction motors and particularly to the large rotary members, or rotors of the squirrel-cage type, in-

tended for high speeds of rotation.

In induction motors of ordinary sizes and.

speeds the construction and weight of the rotary members or rotors are very important. In ,such machines the cores of the rotors 'are .made up of "punched laminae which are heldbetween cast iron end plates the Whole being clamped together by long. bolts.

In rotors of the squlrrel-cage type the windings consist of conductor bars and lating members.

short-circuiting rings .the latter bein usu-- ally seated on ribs or. brackets integra with the spider. The parts of the'rotor and stator are cooled by the fan-like action of the rotor the endsof the machines being usually provided with some form of venti- In some machines the brackets on which the rings rest serve as fan-blades, and in others special fan-blades are mounted on the ends of the rotor.

In large machines, the rotors of Which are designed for very high eripheral speeds, it is quite essential that t e rotors be made Very strong and. compact. At the same time the structures must be carefully designed not be directed against the parts necessaryto be cooled. In some ma ines this difiiculty is, due to the fact that the ventilating members are not sufiiciently near the'periphery oi the'rotor'while in others it is due to the fact that the air currents are prevented from reaching the desired arts onaccount of-the interference of over ang ing parts of Specification of Letters Patent.

Application filed August a1. 1906. Seria1 No. 332.772.

- is so constructed thati jvhen rotated rotor; and Fig. 3 is a sectional view of one .which is mounted the slotted core 11 conends of which extend beyond the ends of the to the oylindric BULLOCK ELECTRIC MANUFACTUItINCr COM- the rotor, particularlyv theI'short-cn rings. Therefore, toobtain the ax um capacity from the motors, it is .lltq ssary thatthe rotary members he so designed and constructed as to v obtain the maxi w cooling effects when in rotationr",

One of the objects ofiny. invention; provide a rotary member for induction noptors which consists of few p ar ts is sim plei z n construction, and compact,i and designed so as to readily Withstand thestrains due to centrifugal action. A further object is. to p rovide a jrotar memberfor large induction motdrs wlgric i cient draft of air is created, andgfi against the arts of the rotor and st prevent a high rise of temperature My invention consists in the e a1; s "of construction and in the combinations and arrangements of parts described.- in they specification and set for th in the appends calms. 1; I

For a better understanding of my nv tion referenceis had to, the accompany ng I drawing in which H Figure 1 is a partial end elevation of a squirrel cage rotor equipped with my invention, parts beingbroken away; Fig. 2 isa partial longitudinal section of the stator and of the end members employed in my invention. l

Referring noW to the fi ures of'the draw 1ng; I have shown at 10t e rotary shaft on sisting of groups of laminate. The core 11 is adapted to rotate at high speed Within the stator core 12 which carries the stator Windmg 13. Located in the slots of the rotor core are the usual conductor bars 14 the core. At 15 are shown end members which serve as short-circuiting means for the conductor bars, as end clamping heads for the laminae of the core, and as ventilating memhere forcreating air currents, to cool the rotor and stator. In this instance the end members 15 consist'of 'rings, each having a cyhndrical portion 16, to which the ends of the conductors are secured by bolts '01-". rivets 17, and a portion 18 at right aiigles a portion 16- and as' he'rc' shown parallelwith the laminae of the'.oo le..

the structures. heretofore employed and by Letters Patent is 1. In a rotor, a laminated core, cond'uctors located in said core, short circuiting which is very compact and able to withstand the stresses due" to centrlfugal action.

-Furthermore, the radial blades 19 are located in the most advantageous position for coolin the rotor and stator since they are'near t 'e conductor bars, in contact with the laminae, and between the laminae and portions. 18 of the rings. These portions 18- can in no manner interfere with'the circulation'ofair, instead, they tend to guide the air outward. r

If desired the rings may be built of a plurality of sections.

I do not wish to 'be confined to the exact details shown but aim in my claimsto cover all modifications which do not involve a departure from the spirit and scope of my invention.

- 'What I claim as new and desire to secure rings for said conductors, said rings having integral fan -"blades extending therefrom toward and into enga ement with the end lamina of the core, an I means for clamping the rings and laminae together. f 2. Ina 'rotor for induction motors, a

slotted laminated core, conductor bars located in the slots of the core, short-circuiting rings for said bars, said rings having substantially radial ribs in engagement with the end laminae of the core, and bolts or rods for clamping the core and rings together.

i 3. In a'rotor for induction motors, a slotted laminated core, condiictor bars located in the slots of the core, and combined shortcircuiting rin s and end-heads clam ed to each side of t e core, said combine shortcircuiting rings and end-heads formed with a portion located in a lane parallel to the laminae of the core an having radial ribs which act as fan-blades the fan-blades being located between said parallel portion and the core.

4. In a rotor for induction motors, a slotted core, conductor bars located in the slots of. the core, combined short-Circuiting rings and end-heads clamped to the laminae, .and radial ribs servi as fan-blades on the inner sides of the rings and engaging the end laminae.

5. In a squirrel-cage rotor of an induction motor, a slotted core, conductor-bars located in the slots of the core, short-circuitin rings for the ends. of theconductors, sai rings having radial ribs or blades on aging the end laminae, and bolts or rods assing through the radial ribs or blades and amines --for c ampi'n the'parts tightly to ether,

whereby sai rings serve also as en -heads for the laminae and as'ventilating members. In testimony whereof I aflix my signature,

in the presence of two witnesses.

BERNARD A. BEHREND.

Witnesses:

LAUnA E. WEBB,

LAURA E. Watch. 

